Gneiss
Gneiss (High-grade Metamorphic Rock)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade Metamorphic Rock)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Quartz Pebble (with Mica or Iron staining)
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (SiO2 based)
Geode (Unopened)
Silica-rich Concretion (primarily SiO2)
Fuchsite
Chromium-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2
Desert Rose (Gypsum/Baryte)
Hydrated Calcium Sulfate (CaSO4·2H2O)
Quartz Geode with Goethite/Hematite
Silicon Dioxide (SiO2) with Iron Oxides
Fire Opal in Host Rock
Amorphous Hydrous Silica (SiO2·nH2O)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Sunstone
Oligoclase (Plagioclase Feldspar), (Na,Ca)(Si,Al)4O8
Amethyst
Silicon dioxide (SiO2) with iron impurities
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Malachite with Chrysocolla
Copper carbonate hydroxide (Cu2CO3(OH)2) and Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Smoky Quartz (Herkimer-style)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Sandstone (Quartzose Sandstone)
Sandstone (SiO2 with various trace minerals)
Chakra Tumbled Stone Set
Various (including Amethyst [SiO2], Sodalite [Na8(Al6Si6O24)Cl2], Green Aventurine [SiO2], Red Jasper [SiO2], etc.)
Tiger's Eye
Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2
Pyrite
Iron Sulfide (FeS2)
Green Calcite
Calcium Carbonate (CaCO3)
Sandstone
Arenite
Green Fluorite
Calcium Fluoride (CaF2)
Quartz
Silicon Dioxide (SiO2)
Rough Sodalite
Sodalite, Na8(Al6Si6O24)Cl2
Rhodonite
Manganese silicate: (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Greywacke (River/Beach Pebble)
Greywacke (Impure Sandstone)
Red Jasper
Cryptocrystalline Quartz (SiO2 with Iron oxide inclusions)
Chrysocolla in Matrix
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·nH2O
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Glauconitic Sandstone
Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Lepidolite and Rubellite (Pink Tourmaline)
Lepidolite [K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2] and Rubellite [Na(Li,Al)3Al6(BO3)3Si6O18(OH)4]
Basalt with Quartz Vein
Basalt (SiO2 vein inclusion)
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Basalt-Amugydule (Amygdaloidal Basalt)
Aphanitic Mafic Igneous Rock with Vesicle Infillings
Bumblebee Jasper
Fibrous Calcite with Arsenic and Sulfur inclusions
Sandstone (with garnet granules)
Clastic sedimentary rock (primarily SiO2 with Fe3Al2(SiO4)3 inclusions)
Calcite on Matrix
Calcium Carbonate (CaCO3)